Kohn Anomaly and Electron−Phonon Interaction at the K-Derived Point of the Brillouin Zone of Metallic Nanotubes

详细信息    查看全文

• 作者：Peter M. Rafailov ; Janina Maultzsch ; Christian Thomsen ; Urszula Dettlaff-Weglikowska ; Siegmar Roth
• 刊名：Nano Letters
• 出版年：2009
• 出版时间：September 9, 2009
• 年：2009
• 卷：9
• 期：9
• 页码：3343-3348
• 全文大小：208K
• 年卷期：v.9,no.9(September 9, 2009)
• ISSN：1530-6992

文摘

We applied Raman spectroscopy to investigate the response to electrochemical doping of the second-order D* band in single-walled carbon nanotube (SWNT) bundles. Our study reveals a dramatic increase of the D* band sensitivity to doping upon moving the laser excitation to the red end of the visible spectrum and beyond. Using the double-resonance scattering model, we show that this phenomenon evidences a second Kohn anomaly in metallic SWNTs, located in the K-point-derived region of the Brillouin zone (BZ), which stems from the Kohn anomaly at the K-point of graphene. Our results will be compared to recent doping experiments on graphene with field-effect gating and can be used to investigate the wave-vector dependent electron−phonon coupling in the bulk of the BZ of metallic SWNTs.